I take the bus often between Madison and Chicago, and I've never had any major problems with this company, aside from the occasional delay. It has outlets, and spotty WiFi. The seating is decent, and also good amount of overhead storage if needed. Overall, better than MegaBus.
I would also like to add that on Thanksgiving Day, Van Galder really made sure to have all hands on deck to accommodate all of the holiday travelers. There were a LOT of express buses, and they were efficient in getting us to our destination during the holiday rush.